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81.
J. G. Villa G. Cuadrado J. E. Bayón J. González-Gallego 《European journal of applied physiology》1997,77(1-2):106-111
The effects of physical conditioning on antipyrine clearance were studied in two groups of subjects. Healthy men not engaged
in the systematic practice of any sport were compared with endurance runners (defined as men running >80 km/week). Studies
were carried out at three different periods of the annual plan training at 4-month intervals. Antipyrine was administered
orally and pharmacokinetic parameters were obtained from saliva samples by the multiple-sample method. Endurance performance,
expressed in terms of the maximal oxygen uptake (V˙O2
max), the ventilatory threshold and the 4-mM · l−1 lactate threshold (OBLA), was higher in trained than in control subjects at each of the three periods. Antipyrine clearance
was also significantly elevated and antipyrine half-life reduced in runners during all periods. No significant difference
in V˙O2
max or antipyrine clearance was found between the various periods in either trained or control subjects. Both ventilatory threshold
and OBLA increased significantly along the training period in conditioned subjects. Significant correlations were found between
antipyrine clearance and V˙O2
max, ventilatory threshold and OBLA. In summary, these results indicate an association between aerobic conditioning and increased
hepatic oxidative metabolism of low-clearance drugs.
Accepted: 15 July 1997 相似文献
82.
83.
Anti-mitochondrial antibodies (anti-M7) in heart diseases recognize epitopes on bacterial and mammalian sarcosine dehydrogenase.
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The anti-mitochondrial antibody (AMA) anti-M7 has been shown to occur exclusively in sera from patients with acute and chronic myocarditis. Applying different enzymes of the inner mitochondrial membrane to ELISA, anti-M7-positive sera reacted only with sarcosine dehydrogenase (SD) from Pseudomonas aeruginosa. Testing these sera in the Western blot against a commercially available SD as well as against SD prepared from rat liver mitochondria, a determinant at 42 kD and 90 kD, respectively, was visualized. Using submitochondrial particles (SMP) from bovine heart and rat liver another major determinant at 64 kD could be observed with both antigen fractions. Liver SMP also expressed the SD-related, 90-kD epitope. Sera from patients with other AMA-positive and AMA-negative autoimmune diseases were negative with these different determinants. The identity of the 64-kD epitope on heart and liver SMP as well as the 42-kD polypeptide of bacterial SD and the 90-kD epitope on mammalian SD was proven by absorption studies and by elution of antibodies from the antigen bound to the immobilon sheets after immunoblotting. The SD enzyme activity was not affected by anti-64-kD and anti-42-kD antibodies in vitro. It is concluded that anti-M7 antibodies may be stimulated by an antigen expressed on cardiocytes during an infection which shares epitopes with SD, an evolutionary highly conserved protein. SD-sensitized B cell clones could therefore be triggered by the M7-antigen which shows homology to SD. 相似文献
84.
Lymphocyte proliferation in response to acute heavy resistance exercise in women: influence of muscle strength and total work 总被引:3,自引:0,他引:3
Dohi K Mastro AM Miles MP Bush JA Grove DS Leach SK Volek JS Nindl BC Marx JO Gotshalk LA Putukian M Sebastianelli WJ Kraemer WJ 《European journal of applied physiology》2001,85(3-4):367-373
Little is understood about the immune responses to heavy resistance exercise. The purpose of this investigation was to determine
the influence of physical strength and the ability to do more total work on lymphocyte proliferation after an acute bout of
heavy resistance exercise. A group of 50 healthy but non-strength trained women were recruited for the study and tested for
their one repetition maximum (i.e. 1 RM or maximal mass lifted once). From the normal distribution of strength the top and
bottom 8 women [mean age 22.5 (SD 3.1) years] were asked to volunteer to define our two groups (i.e. high strength and low
strength). The two groups were significantly different (P<0.05) in 1 RM squat strength [low strength 39.9 (SD 4.6) kg, 0.65 (SD 0.08) kg·kg body mass–1 and high strength 72.2 (SD 10.7) kg, 1.1 (SD 0.12) kg·kg body mass–1] but were not significantly different in body mass, age, activity levels, and menstrual status (all in same phase). Each
performed a resistance exercise protocol consisting of six sets of 10 RM squats with 2 min rest between the sets. The 10 RM
loads and total work were significantly greater in the high strength group than in the low strength group. Blood samples were
obtained pre-exercise and immediately post-exercise for test for lactate (significant increase with exercise) and cortisol
(no changes) concentrations with no differences noted between groups. Immunological assays on the blood samples determined
the incorporation of tritiated thymidine by lymphocytes in responses to concanavalin A (ConA), phytohemagglutinin (PHA), and
pokeweed mitogen (PWM). Following the squat exercise, there was a significant decrease in lymphocyte responsiveness to PWM
in the high strength but not in the low strength group for both total proliferation and proliferation adjusted per B or T
cell. On the other hand, lymphocytes from the low strength group proliferated to a significantly greater extent (adjusted
per T cell) in response to ConA and PHA. These data indicate that the heavy resistance exercise protocol reduced the lymphocyte
proliferative responses only in the stronger group of subjects. This effect may have been due to the high absolute total work
and the greater exercise stress created by the resistance exercise protocol in the high strength group. Therefore, individuals
performing at the same relative exercise intensity (i.e. 10 RM) in a resistance exercise protocol may have different immune
responses stemming from differences in absolute total work performance.
Electronic Publication 相似文献
85.
Dendrites and spines undergo dynamic changes in physiological and pathological conditions. Dendritic outgrowth has been observed in surviving neurons months after ischemia, which is associated with the functional compensation. It remains unclear how dendrites in surviving neurons are altered shortly after ischemia, which might reveal the mechanisms underlying neuronal survival. Using primary cortical cultures, we monitored the dendritic changes in individual neurons after oxygen-glucose deprivation (OGD). Two to four hours of OGD induced approximately 30–50% cell death in 24 h. However, the total dendritic length in surviving neurons was significantly increased after OGD with a peak at 6 h after re-oxygenation. The increase of dendritic length after OGD was mainly due to the sprouting rather than the extension of the dendrites. The dendritic outgrowth after 2 h of OGD was greater than that after 4 h of OGD. Application of NMDA receptor blocker MK-801 abolished OGD-induced dendritic outgrowth, whereas application of AMPA receptor antagonist CNQX had no significant effects. These results demonstrate a NMDA receptor-dependent dendritic plasticity shortly after OGD, which provides insights into the early response of surviving neurons after ischemia. 相似文献
86.
87.
K. J. Ullrich F. Papavassiliou 《Pflügers Archiv : European journal of physiology》1986,407(5):488-492
In order to study the characteristic of contraluminal transport of hydrophylic small fatty acids the in situ stopped flow microperfusion technique [12] has been applied. By measuring with 4 s contact time the decrease in the contraluminal concentration of the respective radiolabelled substances the concentration dependence of the influx into the cortical cells was tested. The 4 s decrease in contraluminal concentration of chloroacetate,l-lactate,d-lactate, 3-hydroxybutyrate and acetoacetate was between 26% and 31%. For each substance the percent decrease was the same, no matter whether it was offered in a concentration of 0.1 or 10 mmol/l. Contraluminal disappearance of 0.1 mmol/ll-lactate was not influenced by 5 mmol/l H2DIDS, probenecid, phloretin, mersalyl or cyanocinnamate, but it was significantly (37%) inhibited by 5-nitro-2-(phenyl-propyl-amino) benzoate, a blocker of the nonspecific anion channel. The percent decrease in propionate uptake was somewhat larger — between 36% and 39% — but again not different at 0.01, 0.1, 1.0 and 10 mmol/l. With pyruvate the contraluminal decrease was 20% at 0.1 mmol/l and 31% at 10 mmol/l. The percent disappearance of the aromatic pyrazinoate was 38% and 34% at 0.1 and 10 mmol/l and for nicotinate 42% and 22%, respectively. The disappearance of nicotinate (0.1 mmol/l) was significantly inhibited by 10 mmol/l pyrazinoate and paraaminohippurate (PAH). The data are in agreement with the hypothesis that the hydrophilic small fatty acids traverse the contraluminal cell side by simple diffusion, possibly via the unspecific anion channel [14], pyruvate via the dicarboxylic acid pathway in a cooperative manner and pyrazinoate, as well as nicotinate, via the PAH pathway. 相似文献
88.
Summary The enzyme inosinic acid dehydrogenase (EC 1.2.1. [14]) was measured and partially purified (10- to 15-fold) from normal and leukemic leukocytes. From the normal blood cells, the highest activities could be detected in lymphocytes and bone marrow cells. Dependent on the blast cell count, the leukemic IMP dehydrogenase had a higher mean specific activity than the enzymes of fractionated, immature bone marrow cells, or normal granulocytes. The partially purified enzymes from the various blood cells were apparently identical; they exhibited hyperbolic substrate saturation kinetics and were inhibited by a number of purine nucleotides. For the leukemic blast cell enzyme, theK
m values for the substrates, IMP and NAD+, were 28±11; 227±98 µM, and 34±10; 240±67 µM for the partially purified enzyme from normal, immature bone marrow cells.The hypoxanthine-guanine and adenine phosphoribosyltransferase activities increased in the leukemic cells when compared with mature granulocytes, but nearly always showed similar activities when compared with the fractionated bone marrow cells. Only one of the 30 investigated leukemic patients exhibited a marked decrease in hypoxanthine phosphoribosyltransferase activity of 0.5 nmol/mg/h. The phosphoribosyltransferase-specific activities of the leukemic cells are more variable than for the normal ones and no correlation of enzyme activities and blast cell count was apparent.
Abbreviations A-PRT adenine phosphoribosyltransferase - HG-PRT hypoxanthine-guanine phosphoribosyltransferase - PRPP 5-phosphoribosyl-1-pyrophosphate - ALL acute lymphocytic leukemia - AML acute myelogenous leukemia - CLL chronic lymphatic leukemia - CML chronic myelogenous leukemia - AMMOL acute myelomonocytic leukemia This study was supported by the Deutsche forschungsgemeinschaft Be 458/4 相似文献
Abbreviations A-PRT adenine phosphoribosyltransferase - HG-PRT hypoxanthine-guanine phosphoribosyltransferase - PRPP 5-phosphoribosyl-1-pyrophosphate - ALL acute lymphocytic leukemia - AML acute myelogenous leukemia - CLL chronic lymphatic leukemia - CML chronic myelogenous leukemia - AMMOL acute myelomonocytic leukemia This study was supported by the Deutsche forschungsgemeinschaft Be 458/4 相似文献
89.
W. P. Vanhelder M. W. Radomski R. C. Goode K. Casey 《European journal of applied physiology》1985,54(4):337-342
Summary Five normal men, aged 20–30 years, participated in three types of exercise (I, II, III) of equal duration (20 min) and total
external work output (120–180 kJ) separated by ten days of rest. Exercises consisted of seven sets of squats with barbells
on the shoulders (I; Maximal Power Output
max=600−900 W), continuous cycling at 50 rev · min−1 (II;
max=100−150 W) and seven bouts of intermittent cycling at 70 rev · min−1 (III;
max=300−450 W).
Plasma cortisol, glucagon and lactate increased significantly (P<0.05) during the exercise and recovery periods of the anaerobic, intermittent exercise (I and III) but not in the continuous,
aerobic exercise (II). No consistent significant changes were found in plasma glucose. Plasma insulin levels decreased only
during exercise II. The highest increase in cortisol and glucagon was not associated with the highest
,
,
max or HR; however it was associated with the anaerobic component of exercise (lactic acid). It is suggested that in exercises
of equal duration and total external work output, the continuous, aerobic exercise (II) led to lowest levels of glucogenic
hormones. 相似文献
90.
Morphologic evaluation of the liver in hereditary angioedema patients on long-term treatment with androgen derivatives 总被引:1,自引:0,他引:1
M Cicardi L Bergamaschini A Tucci A Agostoni G Tornaghi G Coggi R Colombi G Viale 《The Journal of allergy and clinical immunology》1983,72(3):294-298
17 alpha-Alkylated androgens are highly effective in preventing attacks in HAE patients. These drugs, however, seem to be implicated in the development of cholestatic jaundice, peliosis hepatis, and liver tumors. In order to assess the risk-benefit balance of the long-term therapy with androgen derivatives, a follow-up investigation was performed in 13 HAE patients. The results of this study indicate that long-term treatment (15 to 47 mo) with low doses of danazol or stanozolol does not induce significant hepatic damage detectable by laboratory tests or liver biopsy. However, the limited number of patients, although in a rather long period of observation, still suggests a careful control and the use of minimal effective doses. 相似文献